Osteoarthritis is a
progressive musculo-skeletal disorder, which affects around 10% of the
population worldwide above the age of 60 years, causing gradual
degeneration bone joints. Cartilages are the flexible soft tissues that
cover the ends of bone in a joint. Over a passage of time, with the
breakdown of cartilages, bones start to rub against each other causing
stiffness, pain and loss of joint movement. A team of researchers from
the Department of Bioscience and Bioengineering at IIT Bombay is working
on cartilage regeneration using naturally occurring biopolymers.
Biopolymers are polymers of natural origin and form hydrogels which
mimic the extracellular matrix (ECM) and promote tissue growth.
Hydrogels are hydrophilic polymeric networks which can absorb water but
are prevented from dissolving due to their cross-linked structure. Many
biopolymers are in fact components of the ECM and can regulate division,
adhesion, differentiation, and migration of cells more favorably than
synthetic polymers.
Dr. Biji Balakrishnan under
the mentorship of Prof. Rinti Banerjee of Department of Biosciences
& Bioengineering has developed an in situ gelling biopolymeric
hydrogel system which can be injected to the site of injury as a liquid,
which solidifies after about twenty five seconds assuming the shape of
the cartilage defect. This biopolymeric hydrogel prepared using
polysaccharides and proteins, acts as a scaffold for regulating
division, adhesion, differentiation and migration of healthy cells
(chondrocytes) in cartilage and helps in the regeneration of the
cartilage.
This technique of generating hyaline
cartilage is chemically and mechanically better in comparison to the
existing techniques. It takes less than a minute to inject the
biopolymers into our body using a syringe mechanism. The biopolymeric
derivatives for the preparation of hydrogels are also easy to
manufacture and are biocompatible. They also produce negligible
inflammation and oxidative stresses. Since the hydrogel gets degraded as
the regeneration of cartilage proceeds, there is no need for any
surgical intervention to remove it. The properties of hydrogel can be
tuned by changing the concentration of biopolymeric derivatives. If
required, growth factors or drug molecules can also be incorporated
within this hydrogel by simple mixing with biopolymeric solution. The
amount of hydrogel to be injected is decided by the degree of cartilage
defect.
Though this approach has been investigated
for cartilage regeneration, it is not limited to it and can be extended
for regeneration of other tissues. Methods used are simple while
circumventing toxicity, stability and scale up issues making this
injectable system feasible, minimally invasive and easily translatable
for therapeutic and regenerative purposes.